Ore concentration.



No. 835,479. PATENTED NOV. 6, 1906.

H. L. SULMAN, H. F. KTRKPATRICK-PIUARD & J. BALLOT.

ORE CONCENTRATION.

APPLICATION FILED JAN.9,1906.

UNITED STATES PATENT OFFICE.

HENRY LIVINGSTONE SULMAN, HUGH FITZALIS KIRKPATRIOK-PICARD, AND JOHN BALLOT, OF LONDON, ENGLAND, ASSIGNORS TO MINERALS SEPARATION, LIMITED, OF LONDON, ENGLAND.

ORE CONCENTRATION.

Specification of Letters Patent.

Patented Nov. 6, 1906.

Original application filed May 29, 1906, Serial No. 262,889. Divided and this application filed January 9, 1906. Serial No. 295,326-

To all whom it may concern:

Be it known that we, HENRY LIVINGSTONE SULMAN, HUGH FITZALIS KIRKPATRICK-PIC- ARD, and JOHN BALLOT, subjects of the King of England, residing at London, England, have invented certain new and useful Improvements in Ore Concentration, of which the following is a specification.

This invention relates to improvements in ore concentration, and this ap lication is a division of an application filed y us on May 29, 1905, Serial No. 262,889.

Several methods are known in which air and other gas is introduced, generated, or liberated in a pulp containing powdered ore in suspension, whereupon the gaseous films or bubbles attach themselves to certain particles, which are thereby caused to float, while other particles are not so floated.

The object of this invention is to improve such processes.

The invention is particularly applicable to the separation of oiled mineral particles from unoiled particles in a pulp; but it is also applicable in some cases in which gaseous bubbles will selectively adhere to certain particles without the use of oil.

Among the previous processes depending upon gaseous flotation is that described in our previous United States patent, No. 793,808, dated July 4, 1905, in which the flotation of oiled mineral particles is brought about by the liberation of a gas in the pulp'containing them.

According to this invention it is found that a convenient method of effecting the liberation or generation of gas-bubbles in such a pulp is to subject the latter to the action of compressed air or other compressed gas in a suitable vessel or apparatus from which the pressure can be subsequently relieved. If, for example, the ore-pulp after agitation with a small proportion of oil or other suitable substance having a preferential aflinity for m'etalliferous minerals be subjected to the action of com ressed air at a pressure of, say, fifty to one undred pounds per square inch and after the lapse of a few minutes for the due solution of the compressed air or a portion of it by the pulp or the liquid be allowed to discharge itself into an open vessel at the normal atmospheric pressure, the whole of the oiled wh1ch the superaerated ul mineral will at once rise to the surface of the pulp as a coherent scum or froth, which can be removed by skimming or by a surface current of water from the gangue, which remains sunk or suspended in the remainder of the pulp. A spitzkasten is a suitable type of vessel into may be discharged. We have foun this method very efficacious in cleaning up finely-divided ore products which have been submitted to oiling. We do not confine ourselves to the use of atmospheric air, as it is obvious that an suitable gas which is soluble in water to a su ficient extent under pressure and which preferentially attaches itself to oiled mineral particles may be employed to thus effect the gaseous flotation of the oiled mineral particles. It is to be undersood that we do not use pressures below the normal atmospheric pressure atthe time being in any portion of the operation.

The accompanying drawing represents in perspective view one form of the apparatus suitable for carrying this invention into effect.

A mixing vessel A (of which there may be several in series) is provided with a rotatable stirrer B. Crushed ore or similar finely-divided mineral is fed into the vessel A. A pipe C, controlled by a tap C, delivers circuit water to the vessel, and in cases where oil is used the oil is introduced through the pipe D in quantity sufficient to produce a thin coating of oil on these mineral particles, for which oil has an aifinity.

The pulp mixed with oil escapes over the lip of a discharge conduit A and passes through the pipe A to a pump E. Hence the pulp is pumped through discharge-pipe E into the closed chamber F, which is constructed to Withstand a considerable internal pressure and is provided with a safety-valve F, the pressure-gage F and a gage-glass F to indicate the level of the pulp in the cham- ,ber. An outlet-pipe G, having a cock G, leads to a series of spitzkastens H, filled with circuit-water.

The operation is as follows: The cock G is closed. Pulp is pumped into the chamber F, which contains air or other gas, and the pumping is continued until the pressure in the chamber rises to, say, fifty to one hundred pounds per square inch. The pressure is sufficient to cause the air or other gas to be dissolved to a considerable extent-in the pulp.

After the la se of a few minutes for thedue solution oft 1e compressed air or a portion of it by the pulp or the liquid the cock G is opened and the pulp is dischar ed into'the open spitzkasten H, where the liquid is of course under atmospheric pressure. The pump E may be stopped during this discharge. The whole of the mineral to which air-bubbles are attachedsay the oiled mineral-at once rises to the surface as a coherent scum or froth. A surface current of water is maintained in the spitzkasten, and the floating material is thus removed and separated from the gangue, which remains sunk or suspended in the li uid.

It is to be un erstood that the expression oil includes any substance, such as oleic acid, which has a preferential aflinity for certain mineral substances over others.

Having thus described our invention, what we claim, and desire to secure byLetters Patent, is-

1. The process of separating powdered minerals from one another which consists in suspending the powdered minerals in a liquid, subjecting the mixture to a gas-pressure and thereafter relieving the pressure whereby bubbles of gas are liberated in the pulp and carry certain minerals to the surface.

2. The process of separating powdered minerals from one another which consists in agitating the minerals suspended in water with a small quantity of 011, subjecting the pulp to a gas-pressure and thereafter relieving the (pressure whereb bubbles of gas are liberate in the pulp an carry the oiled minerals to the surface.

3. The process of separating powdered m nerals from one another which consists in agitating the minerals sus ended in water with a small quantity of oil, subjecting the pulp to a gas-pressure and thereafter distributing the pulp upon the surface of a column of water whereby the unoiled particles sink while the oiled particles adhering to gaseous bubbles float and are thereby separated.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

HENRY LIVINGSTONE SULMAN. HUGH FITZALIS KIRKPATRICK-PICARD. JOHN BALLOT.

Witnesses P. WILLIAMS, H. DJJAMEsON. 

